WHEN I watched the first episode of Broken (BBC1, Tuesday) I thought it was a good story, if a tad sentimental. I was hopeful the weepy hysteria would come down a few notches and let us get stuck into Christina’s torments with a clear head.

We were presented with a tough and caring single mother who works hard for her children.

Then she gets sacked, battered, denied any benefits, has to pawn her wedding ring, and finds her beloved mother dead in bed.

Desperate for money, and half-crazed with grief and stress, she limps down to the Post Office and claims mammy’s pension.

What a valuable story, I thought. Here was the chance to lift aside the grubby curtain of tabloid journalism and trashy daytime chat shows and see what’s really going on. Here’s a single mother who wanders to the dole office with her hand out, gets into fights and indulges in benefit fraud. Here is a big chance, then, to serve up those cliches to a judgemental public and then demolish them – but the opportunity is being wasted.

If we imagine this drama as a big pot of spicy stew, the Christina storyline is a dollop of cayenne pepper. Things are simmering away, hot and red and making your eyes smart, but then the story insists on telling us about Father Michael’s troubled mind.

It diverges from Christina and waters down the flavour.

Sad Father Michael is a big dollop of cream, taking the heat out of the pot. It’s still tasty though, just not as fiery. So on we go, stirring and tasting, and trying to recall how spicy it was earlier. Maybe if we added a bit more cayenne pepper … ?

But we don’t get the chance because, in episode two, yet another story strand barges its way in and waters things down even more. We get the story of a young black man ejected from a mental health unit because of budget cuts. He goes home in distress, starts waving knives about, and gets shot dead.

It’s a horrible story, but it can’t be done justice if it’s just shoved in as a wee subplot. We can’t tackle it in depth, so all it does is weaken the mix yet again. If Father Michael is cream, then this additional story is a big glug of watery stock. By now, the stew is almost flavourless.

Too much has been chucked into the pot, new flavours blanking out others, drowning out the spices, turning it bland.

If too many cooks spoil the broth, then too many subplots spoil the series. I suppose Jimmy McGovern is angry, but cramming in these various storylines suggests he’s lashing out in rage rather than focusing on one and delivering it with deadly precision.

Speaking of being angry, let’s look at Cosby: Fall of an American Icon (BBC2, Monday). This documentary, broadcast to coincide with Cosby’s trial in America, told the story of his rise from poverty to stardom.

The first half of his life seemed glowing and blessed: he was adored by the American public, not only as a comic actor, but as a role model for black people, and as a way to heal the racial divide in that country.

White families found themselves chuckling along with The Cosby Show whereas, as was pointed out, when a black man was seen on American TV he was usually being held face-down by police.

In contrast, The Cosby Show portrayed a black, safe, middle-class family, and this was a revelation to many. Cosby was adored, called “God” and “America’s Dad”. And then things began to sour. After The Cosby Show, he reinvented himself as a philanthropist, and went around America bestowing money here and there, delivering the cash with a helping of self-righteousness.

He positioned himself as a crotchety, grandfather-knows-best figure, who was reprimanding the black community for not straightening up and flying right.

Stop doing drugs! Stand up straight! Tuck in your shirt! Who could blame black people for flinching at this stern moralising from a man who lived a life of wealth and privilege?

The programme simultaneously told the stories of two women who allege Cosby raped them. As is so often the case, they initially feared no-one would believe them. One was a Playboy Bunny at the time, and thought she had no chance of justice: a woman from the racy Playboy world going up against America’s Dad? No chance!

So dark rumours swirled around Cosby. Some cases were launched against him then stuttered to a halt. Nothing really happened until one man, a black comedian, finally got tired of Old Father Cosby and his prissy lectures.

He cracked a joke about Cosby, asking what right Cosby had to lecture black people on morality when he was raping women?

It was meant as a joke, but its consequences were serious: footage of the performance flashed across the world and it seemed like permission had been granted to finally question the sacred and untouchable Cosby.

The absurd deference which protected him was dropped, journalists asked questions, and more women felt able to speak out.

So now he’s on trial, years after the alleged rapes. The women were held back by fear of tackling a powerful, wealthy man who was doubly protected by his persona as the guardian of black America.

It was only when a black person pierced this persona that people felt able to speak.

A silly, throwaway joke on stage was worth more than the consistent claims across the years of his victims. Now there’s something to get angry about.